Introduction to Zephyr Part 4: Devicetree Tutorial | DigiKey

Devicetree is a powerful method for describing hardware configurations in embedded systems, and it’s the heart of how Zephyr manages boards, peripherals, and drivers. In this video, we’ll guide you through the fundamentals of Devicetree, showing you how it all started as part of the Open Firmware initiative and evolved into the standard way that Linux (and now Zephyr) defines hardware. With Devicetree, you gain a clear, flexible way to separate your code from the underlying hardware specifics. You can find a written version of this tutorial here: https://www.digikey.com/en/maker/tutorials/2025/introduction-to-zephyr-part-4-devicetree-tutorial The GitHub repository for this course (including solutions to the challenges) can be found here: https://github.com/ShawnHymel/introduction-to-zephyr/tree/main We’ll walk through the essential concepts: nodes, properties, compatible strings, and the hierarchical tree structure that ensures every piece of hardware is neatly defined. You’ll learn about the “status” and “reg” properties, which help the system understand how to enable a device and where it’s mapped in memory. We’ll also explore aliases and chosen nodes, showing how they simplify references to common hardware like UARTs and consoles. From there, we’ll move into the Devicetree syntax itself. We’ll examine DTS and DTSI files, overlays, and includes—tools that let you compose a complete hardware picture from multiple sources. You’ll see how Zephyr uses these files at compile time to generate a final hardware configuration, streamlining your build process. We also provide you with a hands-on example: defining a simple button in a Devicetree overlay and reading it in your C code. By seeing how to attach a GPIO pin to a “gpio-keys” device and access it from your application, you’ll understand how to leverage Devicetree for real-world projects. You’ll gain insights into bindings, phandles, and how these elements connect abstract declarations to concrete driver implementations. After watching, you’ll be equipped with the knowledge to confidently navigate and modify Devicetree files. This crucial skill will help you build more portable, maintainable embedded firmware, which ultimately helps you scale your projects across different boards and platforms without rewriting low-level code.